In recent years, techniques have been developed for protecting a passenger of a vehicle from a collision force acting on the vehicle. For enhanced passenger protecting performance, there has been a demand for reconsideration of the overall vehicle body structure including doors. As an example of a vehicle door designed to enhance the passenger protecting performance, there is known a “vehicle door structure” disclosed in Japanese Patent Laid-open Publication No. HEI-7-25236.
The disclosed vehicle door has an inner door panel mounted via upper and lower hinges to a vehicle body to move between open and closed positions. The vehicle door has a door lock device for holding the door closed. The inner door panel includes an impact bar extending between the hinges and the door lock device.
When an impact load is applied to the door in a widthwise direction of the vehicle body, that is, when the vehicle body collides with a certain object at either of right and left sides thereof, the impact bar transfers collision energy from front and rear ends thereof to the hinges and the door lock device to thereby alleviate or reduce the collision.
However, the disclosed vehicle door designed to transfer the collision energy towards the door lock device and the hinges does not take any measure against collision occurring at (or a collision force applied to) a front side of the vehicle body. There is a need to ensure the enhanced passenger protecting performance even when the vehicle body collides with a certain object at a front side thereof.
One may propose to make such a vehicle door deformable to absorb the impact load when a vehicle body collides with the object at a front side thereof. Even in such a case, the door lock device needs to reliably unlock the vehicle door.
What has been needed is a vehicle door which provides an improved performance of protecting passengers from a collision occurring at a front side of a vehicle and which includes a door lock section designed to ensure that the vehicle door is unlocked even after subjected to a collision force.